Modern Techniques for the Synthesis of 6H-Indolo[2,3-b]quinoxaline from Aryl-1,2-diamines and Indoline-2,3-diones and their Reported Pharmaceutical Activities (Part II): A Review

Indolo[2,3-b]quinoxalines belong to a class of heterocyclic compounds with significant promise in medicinal chemistry and materials science due to their different biological and structural properties. This review reports various catalytic methodologies for the synthesis of indolo[2,3- b]quinoxalines, including the use of acids, metal catalysts, ionic liquids, and nano-catalysts. The protocols discussed involve one-pot syntheses, principles of green chemistry, and the efficient recycling of catalysts. The improvements in catalytic methods not only increase the yield and purity of the products but also contribute to the sustainability and ecological friendliness of the synthetic procedures. Moreover, the pharmaceutical properties, including anticancer, antitumor, antibacterial, and antifungal activities, as well as the enhancement of glucose utilization and reduction of insulin resistance, of some synthesized indoloquinoxaline compounds are also outlined.